Question

Use the graphical method to find the value of k, if:
(5, k - 2) lies on the straight line x - 2y + 1 = 0

Answer 1

x - 2y + 1 = 0
⇒ 2y = x + 1
⇒ y = `(x + 1)/(2)`
The table for x - 2y + 1 = 0 is

X	1	3	5
Y	1	2	3

Plotting the above points in a graph, we get the following graph:

From the above graph, it is clear that
k - 2 = 3
⇒ k = 5.